Maryam Azarakhshi; Jalil Farzadmehr
Abstract
Meteorological drought affects the water resources of the basin with a time delay, which leads to the occurrence of hydrological drought. Assessment of rainfall variability and drought is necessary to determine the existing water crisis and water resources management. This study was done in 42 watersheds ...
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Meteorological drought affects the water resources of the basin with a time delay, which leads to the occurrence of hydrological drought. Assessment of rainfall variability and drought is necessary to determine the existing water crisis and water resources management. This study was done in 42 watersheds of Khorasan Razavi province during 1975 to 2015 years to determine the temporal relationship between meteorological and hydrological drought. The hydrological drought severity was calculated with SDI index and meteorological drought was calculated with SPI index. The trend of precipitation and discharge was investigated with Mann-Kendall test. The temporal relationship between the mentioned indices was studied with Pearson correlation coefficient as simultaneously and with a time delay from one to 12 months. The results of Mann- Kendall test were indicative the negative trend of discharge in all watersheds and the most negative slop (-0.052) occurs in PolKhaton watershed. A combination of positive and negative trends in precipitation changes was observed in the study areas. However, the calculated positive trends were not significant at the 95% level in any of the watersheds. In 36.5% of the studied watersheds, no significant correlation coefficients were obtained at 95% level between SDI and SPI. In 60% of the studied watersheds, the highest correlation coefficient between precipitation and discharge with one-month delay, in 25% of watersheds without time delay, in 12.5% of watersheds with 2 months’ time delay and in 2.5% of watersheds with a time delay of 12 months were obtained.
Mohammad Ansari Ghojghar; Masoud Pourgholam-Amiji; Shahab Araghinejad; Banafsheh Zahraie; Saman Razavi; Ali Salajegheh
Abstract
Due to the growing development of meta-models and their combination with optimization algorithms for modeling and predicting meteorological variables, in this research four metaheuristic optimization algorithms of Particle Swarm Optimization (PSO), Genetics Algorithms (GA), Ant Colony Optimization for ...
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Due to the growing development of meta-models and their combination with optimization algorithms for modeling and predicting meteorological variables, in this research four metaheuristic optimization algorithms of Particle Swarm Optimization (PSO), Genetics Algorithms (GA), Ant Colony Optimization for Continuous Domains (ACOR) and Differential Evolutionary (DE) were combined with the adaptive neural-fuzzy inference system (ANFIS) model. The performance of four combined models developed with ANFIS model to predict the Frequency variables of Dust Stormy Days (FDSD) on a seasonal scale in Khuzestan province in the southwest of Iran was evaluated. For this purpose, hourly dust data and codes of the Word Meteorological Organization were used on a seasonal scale with a statistical period of 40 years (1980-2019) in seven synoptic stations of Khuzestan province. The results of good fit indices in the training and testing phase showed that there is no significant difference between the ANFIS method and other combined models used. R and RMSE values of the best combined model (ANFIS-PSO) from 0.88 to 0.97 and 0.10 to 0.19, respectively, and in the ANFIS model from 0.83 to 0.94 and 0.11 to 21, respectively, were variable. The results also showed that the combination of optimization algorithms used with the ANFIS model does not significantly improve the results of the model compared to the individual ANFIS model.
Mohsen Bagheri Bodaghabadi; Mohammad Jamshidi; Zohreh Mosleh
Abstract
Soil organic carbon (OC) is one of the most important soil properties, especially from an environmental point of view. For this reason, OC modeling and estimating has been highly considered. In modeling, application of pedotransfer functions to estimate soil properties from the other ones have an important ...
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Soil organic carbon (OC) is one of the most important soil properties, especially from an environmental point of view. For this reason, OC modeling and estimating has been highly considered. In modeling, application of pedotransfer functions to estimate soil properties from the other ones have an important place in soil science. Unfortunately, not much attention has been paid to the valuable data that are obtained with the least cost and time in the soil profile description. The aim of this study was to determine the importance of data that obtained from soil profile description to estimate the soil organic carbon in Dehgolan region in Kordestan Province. For this purpose, 30 pedons were excavated and described. Soil samples were collected from different horizons and soil properties such as texture, pH, EC, CCE and gypsum were determined. Modeling was performed in three scenario including laboratory data, data of soil profile description and application of laboratory and soil profile description data simultaneously. The results showed that based on laboratory data, soil organic carbon has a significant relationship with silt and CCE properties with a coefficient of determination about 25% (R2 = 0.25); While, the two soil profile description data of soil color (chroma) and genetic horizon with coefficients of determination about 65% (R2 = 0.65). With compilation of laboratory and soil profile description data the coefficient of determination was also obtained 65%. This level of accuracy clearly shows the value and importance of data related to the soil profile description data.
Reza Badizadegan; Saeed Reza Khodashenas; Kazem Esmaili
Abstract
In this study SWMM software has been calibrated with real meteorological and hydrometric data at the North of Tehran basins and simulation parameters have been obtained. For this purpose, five rainfall events and runoff data related to these rainfalls, recorded at the outlet of Zargandeh catchment were ...
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In this study SWMM software has been calibrated with real meteorological and hydrometric data at the North of Tehran basins and simulation parameters have been obtained. For this purpose, five rainfall events and runoff data related to these rainfalls, recorded at the outlet of Zargandeh catchment were used. This model is calibrated with three events and verified with two other events. Also, in this simulation the peaks of flood, outflow hydrographs, runoff volumes and peak flood times is obtained. The root mean square error are obtained for outlet hydrographs for the first to fifth events were 0.05, 0.22, 0.4, 0.37 and 0.16, and the Nash-Sutcliffe coefficient are obtained 0.91, 0.94, 0.93, 0.9 and 0.94, respectively. Also, the percentage of difference of the flood discharge peak modeling and observations for first to fifth events are calculated 7.33%, 9.69%, 5.8%, 5.6% and 9.93% and for runoff volume, this percentage difference are calculated -8.82%, -3.08%, 8.8%, -19.43% and 5.11%, respectively. Based on these results, the performance and application of this model to simulate runoff in this area is acceptable and can be used to manage and control urban runoff.
Nikbibi Bozorgzadeh; Mohammad Reza Rigi; Mohammadreza Sasouli; Farhad Zolfaghari
Abstract
Nowadays, the destructive factors of the environment and natural resources are so widespread that the alarm of destruction of these natural wonders is sounded all over the world. Due to the importance of this topic, the study was conducted to estimate the willingness to pay of local communities to conserve ...
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Nowadays, the destructive factors of the environment and natural resources are so widespread that the alarm of destruction of these natural wonders is sounded all over the world. Due to the importance of this topic, the study was conducted to estimate the willingness to pay of local communities to conserve and restore desert areas of Gosht plain in Saravan in order to attract people's participation to finance projects for the preservation and rehabilitation of desert areas. The sampling process was conducted using Cochran's formula with 303 samples by simple random sampling method. Conditional valuation method and Logit model were used to estimate the people’s willingness to pay. The results showed that gender, education, participation in rural government institutions, employment of trusted executives, the history of participation in educational-developmental classes, being native, income and directly being beneficiaries from the environment of the region has a positive and significant effect on the willingness of people to pay for Gosht plain protection. The variable of age and suggested amount had a negative and significant effect on willingness to pay, but the size of household had no significant effect on willingness to pay. Moreover, the variables of existence of a management organization for participation, acquaintance with the environment, having environmental literacy, and government financial support of the projects had a positive and significant effect on the willingness to pay for the Gosht plain protection. The average of peoples’ willingness to pay monthly in 1398, was obtained 113890 Rials per each person.
Mohammad Chizari; seyede somaye Bathaiy; Hasan Sadighi; Amir Alambeigi
Abstract
The climate change phenomenon is considered as one of the important environmental challenges in the 21st century. The most impacts of this phenomenon are focused on industries and establishments such as agriculture and fishery that is depended on natural resources. Resilience considered as a practical ...
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The climate change phenomenon is considered as one of the important environmental challenges in the 21st century. The most impacts of this phenomenon are focused on industries and establishments such as agriculture and fishery that is depended on natural resources. Resilience considered as a practical approach for compatibility of this phenomenon and the creation of sustainable development. Since networks, especially formal networks such as institutional networks, can play a key role in creating and promoting resilience against climate change, the present study is conducted through a network analysis approach and with the aim of fundamental analyses in the field of resilience against climate change. The statistical population of the present study consists of the small beneficiary owners in Tarom County in Zanjan province. Through network analysis, the dominant statistical method of the research considered as the sociometry and extraction of network centrality indices. According to the findings, two agencies namely Agriculture Jihad Organization, and Banks and Credit and Financial Institution play a major role in the educational information network and technical services, respectively. In the financial facilities network, banks and credit and financial institutions, and the Agricultural Jihad Organization rank first and second in providing the financial services and consulting, respectively. The findings demonstrated that many institutions that can play a constructive role in the field of resilience against climate change, such as the insurance organization, have been secluded and marginalized.
Abdolhamid Hajebi; Mohammad amin Soltanipoor; mohammad fayaz
Abstract
In order to investigate the preference value of plants, this study was conducted in Sirik rangeland in Hormozgan province. To determine the preferred value in this region, two methods of timing and production and consumption of plant species were used. The results of analysis of variance of the preferred ...
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In order to investigate the preference value of plants, this study was conducted in Sirik rangeland in Hormozgan province. To determine the preferred value in this region, two methods of timing and production and consumption of plant species were used. The results of analysis of variance of the preferred value in both timing methods (using a video camera) and the operating percentage yielded the same results. Because in both methods, there was no statistically significant difference at the level of 5% between the years and months of the study and only a significant difference between species. In the chronological method, Sphaerocoma aucheri with statistically assigned the highest mean (29.8%) along with annuals with an average (28.9%) were placed in a class statistically, followed by Moltkiopsis ciliata and Cenchrus pennisetoformis 9.3 and 7.8, respectively. In the method of exploitation percentage, the highest exploitation percentage was Cenchrus pennisetoformis with 52.9%, although with Heliotropium bacciferum with 49.6%, Moltkiopsis ciliata with 45.8%, Sphaerocoma aucheri with 44.6% and Cyprus conglomeratus with 44.5% were in a group. In the Sirik region, Sphaerocoma aucheri was one of the high density and high consumption species and Cenchrus pennisetoformis was the low density and high consumption species. Sphaerocoma aucheri was in the first place in terms of preference value, but it should be noted that livestock tends to graze more than annuals at the beginning of the growing season and at the end of the growing season with drying or seeding of grasses, annuals are received less attention.
Esfandiar Jahantab; Maryam Zahedifar; Mohsen Farzin
Abstract
Study of important soil properties and vegetation attributes can give us awareness of the potential of rangelands and make it possible to determine their condition. O In this regard, the present study was carried out with the aim of studying the structural and functional attributes of different growth ...
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Study of important soil properties and vegetation attributes can give us awareness of the potential of rangelands and make it possible to determine their condition. O In this regard, the present study was carried out with the aim of studying the structural and functional attributes of different growth forms on soil surface indices in the Mianjangal Catchment, Fasa. Eleven soil surface indicators were measured along three 100-meter transects using Landscape Function Analysis. The measured factors were classified to assess functional potentials (stability, infiltration, nutrient cycle). Structural attributes including number of patches, length and width of patches, the percentage of patch length to the transect length, patch area index and organization index were investigated. In general, four ecological patches including shrub, bush, grass and forb and the space between the patches (bare and litter) were identified in the study area. The organization index of patch area index were 0.41 and 0.03 in the study area respectively. The results showed that plant patches with different growth forms had different effects on ecosystem function. The growth form shrub had the highest stability, which had a significant difference with other growth forms. In terms of infiltration index in the study area, there were no significant differences between ecological patches with shrub and grass growth forms. Soil nutrient cycle also had a significant difference between ecological patches and also inter-patches. The shrub growth form had the highest amount of nutrient cycle.
Ali Rajaee; Baharak Motamedvaziri; Aliakbar Nazariye samani; Hasan Ahmadi
Abstract
In this study, 18 variables affecting avalanches have been studied. These variables are related to the conditions: geomorphological and topographic, climatic, snow and also Some activities are related to human factors. In this study, the avalanche risk map was prepared and analyzed using the risk model ...
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In this study, 18 variables affecting avalanches have been studied. These variables are related to the conditions: geomorphological and topographic, climatic, snow and also Some activities are related to human factors. In this study, the avalanche risk map was prepared and analyzed using the risk model (HEV) and the variables affecting the occurrence of avalanches. Avalanche hazard map was prepared using three models: AHP, Garp and MaxEent. Based on three risk factors for avalanches, obstacles in the avalanche route and also sensitivity to avalanches, a risk map was prepared. Comparison of the results with field visits and avalanche occurrence areas and past statistics and information indicate the accuracy of the hazard map with 93.85% accuracy by the AHP method. One of the most important variables in avalanche occurrence in this area is the slope. Then, using two maps of avalanche risk elements and avalanche susceptibility map and avalanche hazard map, snow avalanche risk map has been prepared. The results showed that the avalanche hazard map has a very inherent difference with the avalanche risk map. Areas in the low-hazard category on the avalanche risk map became more important in the avalanche risk map. The most important reason is the existence of endangered elements and the development of residential lands in this area over the past few decades
Emad Zakeri; Hamidreza karimzadeh; Seyed Alireza Mousavi
Abstract
Cover-management factor (C) is one of the most important influential factor on soil erosion using the Revised Universal Soil Loss Equation (RUSLE) model. C-factor is challenging to determine based on the proposed procedures due to lack of accurate information. Vegetation cover map can be used to estimate ...
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Cover-management factor (C) is one of the most important influential factor on soil erosion using the Revised Universal Soil Loss Equation (RUSLE) model. C-factor is challenging to determine based on the proposed procedures due to lack of accurate information. Vegetation cover map can be used to estimate C-factor, but preparing a suitable mapping of vegetation cover is challenging in many situations. Therefore, in this study vegetation cover map was prepared and compared using the k Nearest Neighbor (k-NN) algorithm, linear regression (LR) and linear stepwise regression (LSR) in the study area. In regression methods, 17 vegetation and environmental indices were prepared and their relationships were investigated. The results of comparing the three methods showed that the k-NN method has better results than other regression methods due to its highest overall accuracy (83.3%) and kappa coefficient (75.9%) therefore, it was used to produce C-factor map. Results showed that the k-NN was very promising for mapping vegetation canopy cover in the arid and semi-arid areas. The results showed that among vegetation indices NDVI had the highest correlation (0.82) with percentage vegetation cover. Also, in the k-NN method, the Euclidean distance metrics in k = 9 has better results than the other two Fuzzy and Mahalanobis distances and can be used to estimation of vegetation cover map.
Manizheh Razavi Hosain Abad; Alireza Amirian Chekan; Mohammad Faraji; Jamal Mosavian
Abstract
Soil aggregate stability and its spatial distribution can be considered as a good indicator for assessing the results of measures conducted for mitigation soil erosion. This study was conducted in two adjacent sites in Chahmari region, Kuzestan province. At one site afforestation and contour furrowing ...
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Soil aggregate stability and its spatial distribution can be considered as a good indicator for assessing the results of measures conducted for mitigation soil erosion. This study was conducted in two adjacent sites in Chahmari region, Kuzestan province. At one site afforestation and contour furrowing were conducted to control soil erosion and the adjacent site with no controlling measures was considered as control. A total of 150 soil samples were collected from the surface layer (0-5 cm) of two sites and mean weight diameter of aggregates (MWD) were measured using dry and wet sieving (MWDd and MWDw, respectively). Based on digital soil mapping (DSM) approach and to map MWD spatially, several environmental covariates were derived from a Landsat 8 image and a digital elevation model (DEM). Two machine learning algorithms including artificial neural networks (ANN) and regression trees (RT) were used to predict MWD with covariates as inputs. Results indicated a significant difference between MWDd in two sites, but no significant difference was found between MWDw. Correlation analysis revealed no correlation between MWDw and all terrain attributes derived from the DEM, but significant correlations were obtained between MWDd and some terrain attributes. Most covariates derived from Landsat images had significant correlation with both MWDw and MWDd. ANN and TR had relatively high and almost the same accuracy in predicting MWDw, but in predicting MWDd, ANN was superior to RT. In general, the findings showed good performance of DSM techniques in predicting and spatial mapping of MWD.
Mohammad Tahmoures; davud nikkami
Abstract
Erosion and sedimentation phenomena are two inevitable phenomena of watersheds that are subject to complex factors. Identifying these factors and recognizing their effect on erosion and sediment will help in better planning to reduce the damage caused by erosion and sediment in a basin. In this study, ...
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Erosion and sedimentation phenomena are two inevitable phenomena of watersheds that are subject to complex factors. Identifying these factors and recognizing their effect on erosion and sediment will help in better planning to reduce the damage caused by erosion and sediment in a basin. In this study, to determine the factors affecting sedimentation, the Urmia Lake watershed was selected as the study basin. After identifying 30 characteristics affecting the sedimentation of sub-basins of the study area, including hydrological, physiographic, geomorphological, geological and soil characteristics, climate, land use and vegetation as independent variables, the amount of sediment produced in each sub-basin. Was identified as a dependent variable. Using factor analysis, principal component analysis (PCA), cluster analysis and stepwise multivariate regression between selected independent variables and dependent variable using SPSS software Statistical relationship was obtained between sedimentation of sub-basins and watershed characteristics. According to the selected regression model, it is determined that the amount of sediment in the watershed of Lake Urmia to five factors of agricultural land area (rainfed, irrigated and orchards), the area of sub-basins, the total area of erosion and Quaternary structures, average discharge The annual and basin form factor depends on the fact that these five factors control 89% of the sediment production changes in the selected sub-basins, which is significant at the 5% confidence level. In general, the factors affecting erosion and sedimentation of the Urmia Lake watershed can be divided into three groups: human factors and land use change, geology and physiography.
Pedram Attarod; Mahdieh Garoosiha; Mohammad Javad Mehdikhani; Samira Beiranvand
Abstract
We investigated the trend analysis of rainfall characteristics in the Hyrcanian region of northern Iran in a 33-years period (1987 to 2019). Annual, seasonal, and three 11- years periods (1987-1997; 1997-2008; 2008-2019) were analyzed using data recorded at eight synoptic weather stations of Astara, ...
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We investigated the trend analysis of rainfall characteristics in the Hyrcanian region of northern Iran in a 33-years period (1987 to 2019). Annual, seasonal, and three 11- years periods (1987-1997; 1997-2008; 2008-2019) were analyzed using data recorded at eight synoptic weather stations of Astara, Rasht, Anzali, Ramsar, Noshar, Babolsar, Ghaemshahr, and Gorgan. The Mann–Kendall (MK) non-parametric test was used to determine the rainfall trends. The mean annual rainfall was 1143 mm with the highest and lowest amounts recorded in Anzali (1694 mm) and Gorgan (529 mm), respectively. The MK test demonstrated no significant trends for annual rainfall in each station and the whole region (MK value: 0.32). Rainfall of 11-year periods showed slight differences (1140, 1145, and 1146 mm for the three consecutive periods). Rainfall and the number of annual events per year illustrated positive significant correlations in all weather stations (mean r = 0.58). The mean annual number of rainfall events was 118 with a mean rainfall event of 9.5 mm increased by approximately 0.5 mm (5%) during the recent period. In the Hyrcanian zone, 21% and 31% of the annual rainfall were less than 10 mm and larger than 40 mm, respectively. 34% of yearly rainfall (383 mm) was recorded in the first half of the year and the largest amount of seasonal rainfall was in autumn (43% of total annual rainfall). Plant communities, forest ecosystems, and agricultural activities in the Hyrcanian region will definitely be affected by any change in precipitation.
mahshid souri; payam najafi; javad motamedi; saeedeh nateghi
Abstract
To determine these factors, the DEMATEL was used. To determine the most influential factors, several criteria such as slope, slope direction, height, type of cover, density of cover, percentage of cover, human population, proximity to roads, proximity to residential areas, proximity to agricultural lands, ...
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To determine these factors, the DEMATEL was used. To determine the most influential factors, several criteria such as slope, slope direction, height, type of cover, density of cover, percentage of cover, human population, proximity to roads, proximity to residential areas, proximity to agricultural lands, proximity to water resources, The type of employment of the natives and the use of the lands were used. The various steps of the decision evaluation method included forming the mean matrix, calculating the effect matrix of non-scaled direct relationships, calculating the total matrix (total direct and indirect effects matrix), calculating the impact matrix and the impact rate, and determining the order of effectiveness and impact. Based on the obtained results, among various factors, land use factor (3.9308) has the most impact and factor for slope has the least impact (1.0475) on the fire phenomenon. Based on the results of the present study, land use factors and human population have more interaction with other fire factors and the weight of these factors is more on the occurrence of fire phenomenon. Also, based on the results of the communication vector, which represents the certainty of a criterion as an influential criterion, the factors adjacent to the road (1.43) and height (0.6) have the greatest impact .The most important application of this information is the use of this information in the preparation of fire risk maps.
Samaneh Sadat Mahzooni Kachapi; Pejman Tahmasebi; Ataollah Ebrahimi; Mohammad hasan Jouri; Mohsen Faal; Reza Omidipour
Abstract
Ecological processes at different scales led to heterogeneity in the landscape by changing the pattern of the landscape structure. These would result in fragmentation and disintegration of landscape structures and filtering biodiversity characteristics such as species functional diversity. We performed ...
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Ecological processes at different scales led to heterogeneity in the landscape by changing the pattern of the landscape structure. These would result in fragmentation and disintegration of landscape structures and filtering biodiversity characteristics such as species functional diversity. We performed this study to quantify the patches and classes characteristics of the landscape (metrics) and their impact on indicators of species and functional diversity. Sampling was performed in a semi-steppe rangelands of Chaharmahal and Bakhtiari, where the natural structure of the landscape creates various patches such that classified in seven different classes of plant communities. In each class, different patches were randomly selected and within them 5 to 10 macroplots of 30 * 30 m were randomly-systematically established. Afterwards, 3 plots of 2 * 2 m2 installed in macroplots in order to sample canopy cover and number of species. Taxonomic, functional diversity and functional beta diversity indices were measured using "Vegan", "FD" and "betapart" statistical packages in R software, respectively. The landscape metrics were also measured using Fragstats software. Finally, the relationships between diversity indices and landscape metrics were analyzed using linear regression. The results at the patch level showed a significant negative relationship between the shape and functional diversity indices such as leaf nitrogen weight average and leaf specific surface area weight average. The results at the class level indicate the positive effect of the functional evenness index on the edge density metric as well as the functional beta diversity of the patch richness metric.
Esmaeil Sheidai Karkaj; Esfandiar Jahantab; Zahra Mahmoodi
Abstract
Plant growth and yield in the environment is affected by numerous biotic and abiotic environmental stresses as well as seed dormancy. The aim of the present study was to investigate the effect of seed washing treatments with sulfuric acid and irrigation of seeds with saline water on seed germination ...
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Plant growth and yield in the environment is affected by numerous biotic and abiotic environmental stresses as well as seed dormancy. The aim of the present study was to investigate the effect of seed washing treatments with sulfuric acid and irrigation of seeds with saline water on seed germination of Zygophyllum fabago. According to previous relevant researches, for this purpose, three concentrations of 0, 10 and 20% were prepared for acid washing treatment. For salinity treatment, four levels were considered: 0, 60, 90 and 120 mmol / l. Irrigation with spray water was applied evenly on all pteridia when necessary. Germinated seeds were counted daily and continued until no increase in the number of germinated seeds was observed .Comparison of the mean of the main effect of different levels of acid treatment on the germination percentage of Z. fabago showed that zero and ten percent acid concentration treatments with 59 and 60 percent have a higher value. Regarding the comparison of the mean of the interaction effects of acid and salinity, the results showed that the best treatment combination is zero percent acid and zero salinity of ten and ten millimoles per liter. Therefore, Z. fabago species needs low concentrations of salinity and sulfuric acid for optimal growth. Therefore, it can be used to improve and rehabilitate rangeland ecosystems according to the salinity of the area.
Morteza Saberi; Soheila noori; Fahimeh Rashidi
Abstract
Germination is one of the most important stages of plant growth that may be affected by different stresses in natural environments. This study was kind aimed to investigate the effects of substrate and different levels of gibberellic and indole butyric acid on germination characteristics of ...
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Germination is one of the most important stages of plant growth that may be affected by different stresses in natural environments. This study was kind aimed to investigate the effects of substrate and different levels of gibberellic and indole butyric acid on germination characteristics of Salvadora persica seeds in 2019. Two factors was considered consist of substrate (in four types (1- pit moss, 2 - cocopit and 3 - pit moss 50% + sand 50% 4 - Cocopit 50% + 50% sand), and gibberellic acid (in two levels 250 and 500 ppm) and indole butyric acid (in two levels 250 and 500 ppm). Then, the effect of these two factors and distilled water as the control in three replications on seed germination and seedling growth of Salvadora persica was investigated using a completely randomized factorial design. The results showed that the substrate had a significant effect on germination percentage, root length, shoot length, seedling, fresh root weight, shoot fresh weight and seed vigor index (p < 0.01). Seed pretreatment with gibberellic and indole butyric acid hormones had a significant effect on all studied characteristics. Interaction of substrate type and pretreatment with hormones had a significant effect on germination percentage, root length, shoot length, seedling and seed vigor index (p < 0.01) and had no significant effect on root and shoot fresh weight. The highest germination percentage was obtained in cocopeat and gibberellic acid 250 ppm (73%).
Fatemeh Mohammadabadi; Mahdi Kolahi
Abstract
Social participation is an important factor in the social, economic and cultural development of human societies. Engagement in natural resources management also plays an important role towards sustainable development and is an important approach to achieve goals and to success in natural resource plans. ...
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Social participation is an important factor in the social, economic and cultural development of human societies. Engagement in natural resources management also plays an important role towards sustainable development and is an important approach to achieve goals and to success in natural resource plans. In this regard, this research aims to investigate factors affecting people's participation in the implemented natural resource plans by conducting a questionnaire survey in the counties of Sarakhs (the villages of Bazangan, Zalughal, and Kalateh Awaz), Torbat Jam (the villages of Musa Abad, Tamink Olya, Tamink Sofla, and Kalate Ghazi), and Kashmar (the villages of Jardavi, Baharieh, and Ghochpalang), Khorasan Razavi Province, Iran. For sampling, out of 3077 households of these ten villages, 807 households were randomly selected and surveyed by cluster systematic method. The collected data were analyzed by SPSS and Amos software. Structural equations were modeled for visual and graphic design. The main indices and fitting coefficients of the model were identified. The results of the statistical tests showed that people had willingness to participate in the plans and some factors had a significant impact on public participation in the region, such as economic profitability of the plans, education, employment, social conflicts, and environmental attractions (sig <0.05). As a result, these factors should be strengthened and given more consideration for the future successful implementation of natural resource plans. Finally, identifying these factors in each region will be an important step in the success of any plan.
Asghar Farajollahi; Iman Islami
Abstract
Sustainable livelihood approach is one of the new approaches in the field of sustainable rural development, which has been considered for poverty reduction and improving rural living standards, and their factors have a vital importance and role. Therefore, the aim of this study investigate the effect ...
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Sustainable livelihood approach is one of the new approaches in the field of sustainable rural development, which has been considered for poverty reduction and improving rural living standards, and their factors have a vital importance and role. Therefore, the aim of this study investigate the effect of ecotourism on sustainable rural livelihood in Palangan Village of Kurdistan Province. The statistical population in this study is all persons over 20 year’s old living in the studied village that are 623 peoples. Sampling was done randomly that using the Cochran formula, a total of 238 individuals were selected. A data collection tool was a researcher-made questionnaire that used after confirming the validity by experts' opinion and reliability by Cronbach's alpha coefficient (0.83). Data analysis was performed using SPSS16.0 software. The results of one-sample t-test showed that natural, social and human resources were not in a good condition under the influence of ecotourism in Palangan village. Financial and physical capitals have had a better effects and this effect was only significant in physical livelihood capital. The findings of this study showed that there is a need to improve the tourism situation in the study area in order to achieve sustainable livelihoods and in this regard, principled management, local community participation and the use of ecotourism potentials in Palangan village are necessary.
Ali Mohammadian; Esmaeil Asadi Borujeni; Ataollah Ebrahimi; Pejman Tahmasebi; Ali Asghar Naghipour borj
Abstract
Nowadays, using satellite imagery is one of the fastest and lowest-cost methods in rangeland assessment. Also, remote sensing-based vegetation indices are among the most widely used tools to assess and monitor vegetation changes, especially in the post-fire period, and to map the burned regions in rangelands. ...
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Nowadays, using satellite imagery is one of the fastest and lowest-cost methods in rangeland assessment. Also, remote sensing-based vegetation indices are among the most widely used tools to assess and monitor vegetation changes, especially in the post-fire period, and to map the burned regions in rangelands. The present study was conducted considering the importance and extent of rangelands and the recently increased prevalence of fires in the semi-steppe rangelands of Iran, especially in Chaharmahal and Bakhtiari Province. The main objective of this study was to distinguish and identify the burned areas during 1-3 year and 3-5 year periods to adopt an appropriate post-fire management program in these areas using spectral indices. After calculating the spectral indices, the M statistical parameter was determined to designate the separation capability of the burned areas from the adjacent ones. According to the findings, using NBRT, NBR, and CSI indices is recommended to identify and distinguish the burned areas 1-3 years after the fire from the adjacent areas in semi-steppe rangeland regions of Iran. Overall, these indices are of high efficiency in separating these ranges. Moreover, T.C. Brightness and NBRT indices can efficiently identify and separate the burned areas 3-5 years after the fire. Among the studied indices for both periods of fire in the studied semi-steppe rangelands, the NBRT index showed a high potential for identifying the burned area from the adjacent areas.
Kobr Karimi; Esmail Karamidehkordi; Matthias Buchecker
Abstract
The Carbon Sequestration Project has been an important international initiative for natural resources management and climate change reduction measures over the past two decades.It has tried to involve rural households in all stages of the project to achieve environmental, economic,social and human goals. ...
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The Carbon Sequestration Project has been an important international initiative for natural resources management and climate change reduction measures over the past two decades.It has tried to involve rural households in all stages of the project to achieve environmental, economic,social and human goals. A number of factors can affect relevant stakeholders’ participation in carbon sequestration project activities.This study aimed to investigate the socio-economic factors affecting the participation of rural households in the Qom province, using a survey with a descriptive-correlational approach. A sample of 265 households out of 840 rural households was selected using a simple random sampling method in five villages where this project was implemented.The data were collected using a structured interview technique by a questionnaire and analyzed using the SPSS22 and AMOS software.The results showed that rural people had highly been involved in the less active participation stages, such as expert consultation with council members and village elders, where as they had poor contribution to the projects through collaborative or spontaneous involvements.The most important factors affecting the participation of rural households in the carbon sequestration project were identified to be variables such as social capitals; extension programs; implemented conservation projects; agricultural and non-agricultural diversification initiatives in carbon sequestration projects; the land area of households’ permanent crop; and their agricultural income.Promoting social capital through extension programs, and applying a combination of conservation and livelihood diversification measures can not only strengthen the participation of rural communities in natural resource management projects but also increase the success of these projects.
Bahram Mir Derikvand; Alireza Sepahvand; Hossein Zeinivand
Abstract
In recent years, extensive practices have been done on flood control, erosion and sediment in the fields of research and implementation of watershed management. Therefore, the purpose of this study was to assess the effects of watershed management practices on the characteristics of runoff and suspended ...
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In recent years, extensive practices have been done on flood control, erosion and sediment in the fields of research and implementation of watershed management. Therefore, the purpose of this study was to assess the effects of watershed management practices on the characteristics of runoff and suspended sediment load in two subwatersheds in Ghaleh Gol watershed in Lorestan province, Iran. In this research, for comparing the effect of watershed management practices (WMP) on discharge and suspended sediment load (SSL) from both subwatersheds, the flow velocity was measured and the SSL was sampled directly from the beginning of the rainfall events until the end of them. Results showed that in all measurements, the discharge and suspended sediment load of the southern subwatershed with watershed management practices was higher than the northern subwatershed without such practices. According to the results of ANOVA test, it was found that the difference between discharge peak (P=0.691) and suspended sediment load peak (P=0.840) was not significant in two subwatersheds. Also, according to the results, the difference between specific discharge and specific SSL was not significant (P>0.05). Based on these results, it was found that the implementation of WMP in the study area apparently has no the required performance to reduce the discharge and SSL, and the WMP have lost their performance before the end of their useful life. Therefore, in order to increase the performance of mechanical watershed management practices (MWMP), the biological and biomechanical practices has to be performed simultaneously.
Ali Mohebby; Mahdi Ramezani; Naser Arabzadeh
Abstract
This research was aimed to investigate the populations of Fortuynia bongei in a complete blocks design with three replications in field conditions. Treatments included the populations of Fortuynia bongei collected from Sirch, Koohpayeh, Zarand, Bam and Baghin. The traits including vegetation cover, forage ...
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This research was aimed to investigate the populations of Fortuynia bongei in a complete blocks design with three replications in field conditions. Treatments included the populations of Fortuynia bongei collected from Sirch, Koohpayeh, Zarand, Bam and Baghin. The traits including vegetation cover, forage yield, and seed yield were recorded. Data were analyzed by SPSS software and mean comparisons were performed by Duncan's Multiple Range Test. The results of ANOVA showed significant differences among the populations of Fortuynia bongei collected in this study. According to the results of mean comparisons, the highest percentage was recorded for the Koohpayeh population and the Bam population had the highest yield and seed production. So, these tow population could be recommended for the range lands rehabilitation projects in this area.
Nesar Nasiri; Keivan Asghari; Ali Asghar Besalatpour
Abstract
This study examines spatial and temporal changes in water resources; including blue and green water resources components, taking into account their changes in four main land use in the Zayandeh-rud basin. The spatial and temporal changes were studied using the semi-distributed hydrological model SWAT ...
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This study examines spatial and temporal changes in water resources; including blue and green water resources components, taking into account their changes in four main land use in the Zayandeh-rud basin. The spatial and temporal changes were studied using the semi-distributed hydrological model SWAT (Soil and Water Assessment Tool) by applying the most complete data set developed for the watershed over 20 years and for four different 5-year intervals. Due to the high ability and efficiency of the SWAT model to simulate climatic parameters and surface runoff, the minimum 5-year average of blue water, green water flow, and green water storage at the basin level occurred; in the fourth period 2010-2014 (approx. 15 mm), the second period 2000-2004 (26 mm) and the first period 1995-1999 (30 mm), respectively. On the other hand, the mean values of the blue water component, the green water flow and the green water storage components were estimated to be higher in the western parts of the basin than in the eastern parts. Other findings from this study are the changes of blue water and green water regarding precipitation and land use. For example, the maximum amount of blue water was observed in forests and irrigated agricultural lands, the highest amount of change in green water flow in irrigated agricultural and dry farming lands, and the minimum amount of green water flow in grasslands. Acknowledgment of available water resources, water potentials of an area and critical areas enables comprehensive management of water resources and long-term planning.
TAYYEBEH MESBAHZADEH; Ali Salajegheh; farshad soleimani sardoo; Gholamreza Zehtabian; Abbas Ranjbar; Mario Marcello Miglietta
Abstract
Today, the phenomenon of dust is known as one of the most important natural disasters in arid and semi-arid regions. The long-term effects of this phenomenon on the human health index are referred to as chronic disease. Therefore, studying and identifying the patterns and centers of this phenomenon seems ...
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Today, the phenomenon of dust is known as one of the most important natural disasters in arid and semi-arid regions. The long-term effects of this phenomenon on the human health index are referred to as chronic disease. Therefore, studying and identifying the patterns and centers of this phenomenon seems necessary in these areas. In this study, in order to simulate the dust emission flux to determine the internal and external critical centers in the central plateau of Iran, WRF-Chem model and GOCART wind erosion scheme and storm were used from July 19 to 21, 2015. The results showed that the Arabian deserts in Saudi Arabia, the deserts of Iraq, as well as the Gharegham desert in Turkmenistan and the Helmand region in Afghanistan are among the most important foreign crisis centers affecting Iran's central plateau atmosphere. Also, the Central Desert (Dasht-e Kavir) has been identified as the main source of dust and the southern parts of the Central Loot Basin and the Jazmourian Basin have been identified as the internal sources of dust. The results also showed that in the Central Loot basin, the amount of 6900 micrograms per square meter of dust increases per second due to the erosion conditions.
